Tube-expander.



/ lfltlllllflllllll l ll l /vgggyes.

M Mia W M? PATENTBD SEPT. 25, 1906. O. D. HAND & F. R. FRANSON.

TUBE EXPANDER.

APPLIOATION FILED APR. 20, 1905. RENEWED MAB. 6, 1906.

i j 5 Z 4 2 0 a d a J a J4 a I "UNITED STATES PATENT onnion.

CLIFTON D. HAND, OF RIVERDALE, AND FREDRICK R. FRANSON, OF CHICAGO, ILLINOIS.

TUBE-EXPANDER.

Specification of Letters Patent.

Patented Sept. 25, 1906.

Application filed April 20, 1905. Renewed March 6, 1906. Serial No. 304,526.

To all whom, it ntcty concern:

Be it known that we, CLIFTON D. I'IAND,1' siding at River-dale, and FREDRIoK R. FRAN- SON, residing at Chicago, in the county of Cook and State of Illinois, citizens of the United States, have invented new and useful Improvements in Tube-Expanders, of which the following is a specification.

This invention is an improved device for expanding boiler or similar tubes.

It has for its object to provide an improved construction whereby ball-bearings may be applied to a rotary expander to decrease the friction.

A further object is to form an improved holder for the rollers, so that they will not drop in or out.

A further object is to construct an expander which does not require any driving on the mandrel, but which will draw the mandrel into the tube in consequence of the rotary motion until the tube is expanded sufficiently, when a reverse motion will loosen the mandrel, so that the expander can be removed.

A further object is to produce an expander which will allow a very high rotary speed to be applied to the mandrel to do quick work without injuring the tool.

A further object is to produce an expander that has but few parts, assembled so that they can be easily taken apart to renew the rollers.

In the accompanying drawings, Figure 1 is a side view of the expander. Fig. 2 is a longitudinal section. Fig. 3 is a front end View. Fig. 4 is a section on the line 4 I of Fig. 2.

Referring specifically to the drawings, Y indicates a ta ered mandrel which is inserted in the expanc er when it is desired to expand a tube, it being understood that the device is used for expanding the ends of tubes, so as to tighten the joint where they are connected to the flue-sheet.

A indicates a cylindrical casing having at the front end segmental shoulders, between which the casing is cut away to form recesses a. Inside the shoulders is a recess of, which is adapted to receive the end of a tube X, and the shoulders a a rest against the flue-sheet while the device is in use.

B is a barrel orholder having an axial bore 6 and a tapered front end 6. b represents radial slots set obliquely to the axis of the tool, in which slots are placed loosely the expandingrollers R. Normally these rollers, of which there are preferably three, lie close together inwardly in the position shown in Figs. 2 and 4. The slots are contracted at the inner and outer edges, so that the rollers cannot fall in or out.

C is an enlarged annular part at the rear end of the holder, having recesses c at the front, in which the rear ends of the rollers R enter when the rollers are in an expanded position. a is an interior rib on the casing A, and the part C abuts against the same. The part C is screwthreaded at c.

D is a cap or ball-retainer for the ball-bearings, having a nipple or screw-threaded part (Z, which engages the part C, bringing said part C back against the rib (L The cap D is squared at D to receive a wrench for tightening or loosening the parts. E is a set-screw to hold them. The cap has a shoulder d. This and the rib a, on the casing form a raceway for the balls (1 thus forming ball-bearm e on which the cap revolves.

When the expander is in use, the casing A rests against the end sheet of the boiler, and the ball-bearings thus take up some of the end thrust and lessen the friction. The parts C, D, and B, with the rollers R, all turn together when the mandrel Yis being rotated, the casing A being stationary. The rollers R are mounted obliquely in the grooves, as shown. When rotated, the oblique contact tends to draw the mandrel in, expanding the rollers without necessity for hammering or driving in the mandrel, thus producing the desired expansion, and reverse rotation tends to force the mandrel back and loosen the expander. The thrust and circumferential frictions are sustained mainly by the ballbearings.

I/Vhat we claim as new, and desire to secure by Letters Patent, is

In a tube-expander, the combination with an outer casing, having an inner circumferential rib, and extending forwardly and rearwardly from said rib, a roller-holder rotatable in said casing and having an enlarged rear annames to this specification in the presence of nular part abutting against said rib, a cap tWo subscribing Witnesses. screwed into the said rear part of the holder CLIFTON D. HAND. and extendlng Within said casing behind the 5 rib and having a shoulder opposite the rear FREDRICK FRANSON' side of said rib, forming a raceway, and bear- Witnesses: ing-balls in said raceway. OTTO F. REIOH,

In testimony whereof We have signed our AUGUST C. REIoH. 

